WO2006081778A1

WO2006081778A1 - Fully absorptive acoustic barrier

Info

Publication number: WO2006081778A1
Application number: PCT/CZ2005/000101
Authority: WO
Inventors: Vladimír TOMIS
Original assignee: Tomis Vladimir
Priority date: 2005-02-01
Filing date: 2005-12-30
Publication date: 2006-08-10
Also published as: CZ296461B6; CZ200558A3

Abstract

Fully absorptive acoustic barrier, one-sided or both-sided, consisting of panels (1), which are made of porous sound absorptive material (2) and contain in the sound absorptive material bearing or reinforcing construction (3) of slabs and/or bars and/or meshes of reflective material and/or fibres as a dispersed reinforcement. The parts of the bearing or reinforcing construction have the surface in the plane parallel with the front surface of the panel smaller than 75 % of the total front surface of the panel and at least 50 % of the surface is hidden in the sound absorptive material. Stability of the flat panels in the acoustic barrier is ensured by their attaching to the supporting construction, whose vertical (4) or horizontal elements (5) do not cover the surface of the panels of more then 50%. The panels can be used for construction of acoustic barriers along roads or other noise sources.

Description

Fully absorptive acoustic barrier

Technical field

The invention deals with one-sided or both-sided highly absorptive acoustic barriers, which can be built along roads, railway lines and at other sources of noise in order to protect from the noise behind the wall as well as to protect from the reflected noise on the noise source side.

Background of the invention

So far the absorptive acoustic barriers have been made in the way that the noise absorption has been provided by a layer of sound absorptive material placed at a load bearing slab made of a reflective material and attached to this slab by various means as described in the patents and utility models EP0825302, FR2724401, DE4343687, DE4408177, CZ 10426 Ul, CZ 11726 Ul, US4352457, US5539163. A disadvantage of this solution is that the load bearing slab reflective surface reflects a part of the acoustic waves even if it is. covered with the sound absorptive material layer. It is possible to achieve high values of sound absorption only by increasing a thickness of the sound absorptive material layer. In case that high both- sided sound absorption is required, the thick layer of the sound absorptive material must be on both sides of the bearing wall. There also exist solutions when sound absorptive slab elements are made of a porous material without own bearing structure of the reflective material as described in the patents and utility models CZ 10007 Ul, CZ 10313 Ul, CZ 290500 B6. A disadvantage of these solutions is that the sound absorptive slab elements cannot be of large dimensions and their stability in the acoustic barriers must be ensured by their attachment to a coherent reflective surface or by their positioning in a frame of the reflective material and attaching at columns with reflective surface.

Summary of the invention

The solution according to this invention considerably eliminates the mentioned disadvantages. The core of the invention is that the absorptive acoustic barrier consists of panels, which are made of porous sound absorptive material which contains a bearing or reinforcing construction made of slabs, bars, meshes or dispersed fibres of the reflective material. The elerηents. of the bearing or reinforcing construction have the surface in the plane parallel with the front surface of the panel considerably smaller than the total front surface of the panel and great part of their surface is hidden in the sound absorptive material. The sound transmission loss of the panel is provided by a sufficient thickness and density of the sound absorptive material.

The sound reflective material used in the panel is such a material, that the acoustic barrier made of that material would reach a one-digit value of DLa sound absorption according to the European standard EN ISO 354 smaller than 4 dB, or it is such a material whose sound absorption is worse than sound absorption of the sound absorptive material used in panel. The sound absorptive material in the panels is made of granules with particles sized from 0.1 to 100 mm bound with a bonding agent so that the gaps between the granules are not filled and/or the sound absorptive material is made of fibres of a diameter from 0.001 mm to 2 mm bound with a bonding agent in order that the gaps between the fibres are not filled and/or the sound absorptive material is made of porous material with pores of a size from 0.1 mm to 20 mm, which are at least on the surface opened.

The sound absorptive material in the panel consists of one or more layers while the neighbouring layers consist of the sound absorptive material of a different composition. Common or light weight aggregates, granulates of crushed recycled material - concrete, bricks, rubber, glass, wood and slabs of those materials - can be used in the sound absorptive material.

Polyprophylene, basalt, glass fibres and slabs or mats of these materials can be used in the sound absorptive material.

Binding agents for building purposes - cement, lime, plaster, water glass, synthetic resin, acrylate, asphalt, caoutchouc, synthetic bonding agents and synthetic rubber - can be used as a binding agent.¹

The bearing or reinforcing construction situated in the sound absorptive material of the panel can have a shape of a slab with various holes or a shape of bars, which can be connected to the frames or a shape of mesh made of thin bars or fibres or of fibres as a dispersed reinforcement.

The bearing or reinforcing construction can be made of reinforced or prestressed normal- weight or lightweight concrete, polymer concrete, steel with anti corrosive coating, aluminium or other metals- resistant to corrosion, metal tubes filled with concrete or polymer concrete, plastic, wood or it can be made of composite materials made of glass or carbon fibres bonded with synthetic resin or it can be made of combination of those materials. The reinforcing fibres can be of steel, glass, carbon or plastics.

The surface of parts of the bearing or reinforcing construction in the plane parallel with the front surface of the panel is smaller than 75 % of the total front surface of the panel and at least 50 % of this surface is hidden in the sound absorptive material. The bearing or reinforcing construction is bonded with the sound absorptive material in the panel by means of surface adhesive joint or by means of point mechanical or adhesive joints. The total volume of the dispersed reinforcing fibres is smaller than 50 % of the total volume of sound absorptive material of the panel.

Stability of the panels in the acoustic barrier is ensured by their attachment to the supporting construction whose elements are shaped in such a way that they do not cover more than 50% of front or rear surface of the panel. The vertical elements of. the supporting construction are columns or posts, the horizontal elements are bars, walls or foundation blocks. The panels are set into grooves in these supporting structures or they are attached to the supporting structures by attaching instruments. The supporting structure elements can have a surface of the sound reflective or sound absorptive material. The length of the panels can be up to^' 9 rri^!and the high up to 4.5 m.

The advantage of the solution according to this invention is that the panels of acoustic barrier contain only ^;a¹'sm'all amount of internal reflective surfaces which reduce absorption. By the identical total thickness it is possible to use greater share of sound absorptive material in the parielsi 'Thύs it is possible to achieve higher level of the sound absorption than in case of panels With a continual internal or rear reflective surface or with a peripheral outer reflective framed The sound absorptive material is exploited on both sides so that a both-sided absorptive¹ acoustic barrier is created. Another advantage is that it is possible to produce very lightweight^' panels by use of sound absorptive material of ^■ the lightweight granulate or the' Hghtweight fibres or lightweight porous material and/or when a lightweight bearing or

of the panels is used. The elements have then considerably lower transportation and assembly costs.

Brief description of the drawings

Hg. 1 View _:1 , of tine acoustic barrier according to example 1

Fig. 2 Horizontalrsection A-A through the acoustic barrier according to example 1

Fig. 3 . Vertical section B-B through the acoustic barrier according to example 1

Fig. 4 View ,2 of _[the acoustic barrier according to example 2

Fig. 5 HorizontaJ section C-C through the acoustic barrier according to example 2

Fig. 6 Vertical_. section D-D through the acoustic barrier according to example 2

Fig. 7 , View; 3. of the acoustic barrier according to example 3 ^'.

Fig. 8 Horizontal section E-E through the acoustic barrier according to example 3

Fig. 9 . Vertical section F-F through the acoustic barrier according to example 3

Fig. 10 View 4 of the acoustic barrier according to example 4

^v ' '! i i Fig. 11 Horizontal section G-G through the acoustic barrier according to example 4

Fig. 12 Vertical section H-H through the acoustic barrier according to example 4

Fig. 13 View 5 of the acoustic barrier according to example 5

Fig. 14 Horizontal section I-I through the acoustic barrier according to example 5

Fig. 15 Vertical section J-J through the acoustic barrier according to example 5

Fig. 16 View 6 of the acoustic barrier according to example 6

Fig. 17 Horizontal section K-K through the acoustic barrier according to example 6

Fig. 18 Vertical section L-L through the acoustic barrier according to example 6

Fig. 19 View 7 of the acoustic barrier according to example 7

Fig. 20 Horizontal section M-M through the acoustic barrier according to example 7

Fig. 21 Vertical section N-N through the acoustic barrier according to example 7

Detailed description of the preferred embodiment of the invention

Example 1

Fully absorptive acoustic barrier made of panels I of a length of 6 m, a height of 2.4 m and a thickness of 0.25 m showed in pictures 1, 2 and 3. The panels are made of sound absorptive material 2, with a built-in bearing construction 3 of a frame of bars 3a of reflective material.^' The face surface of the frame bars is 12 % of the total front surface of the panel. The frame is completely hidden in the absorptive material. The absorptive material is placed in the panel in three layers 7, 8 and 9. The surface layers of the absorptive material 7 and 9 are of lightweight aggregate of expanded clay with particles sized 1 to 5 mm bound with synthetic resin. The inner layer of the absorptive material 8 is of lightweight aggregate of expanded clay with particles sized 0.5 to 2 mm bound with synthetic resin. The bearing frame is made of aluminium tubes filled with polymer concrete. Both sides of the panels are profiled with ribs JLO. Stability of the panels in the acoustic barrier is ensured in the way that they are bedded into vertical steel columns 4 with a vertical groove and they are supported by a horizontal concrete bar JL On the front as well as rear column surface there is layer 6 of porous absorptive material of expanded clay granulate with particles sized 1 to 5 mm bound with synthetic resin.

Example 2

Fully absorptive acoustic barrier made of panels 1 of a length of 6 m, a height of 2.4 m and a thickness of 0.24 m showed in pictures 4, 5 and 6. The panels are made of sound absorptive material 2, with a built-in bearing construction 3 of a frame of bars 3a of reflective material. The face surface of the frame bars is 18 % of the total front surface of the panel. 2 % of the frame surface exceeds on the sides from the absorptive material. The sound absorptive material consists of gravel aggregate with particles sized 2 to 5 mm bound with cement bonding agent. The bearing frame is of reinforced concrete. One side of the panel is profiled with ribs IQ, the other is flat. Stability of the panels in the acoustic barrier is ensured in the way that they are set into vertical concrete columns 4 with a vertical groove and they are supported by a horizontal concrete bar 5. On the front as well as rear column surface there is layer 6 of porous sound absorptive material of gravel aggregate with particles sized 2 to 5 mm bound with cement bonding agent.

Example 3

Fully absorptive acoustic barrier made of panels 1 of a length of 6 m, a height of 2.4 m and thickness of 0.2 m with a cut corner showed in pictures 7, 8 and 9. The panels are made of sound absorptive material 2, with a built-in bearing and reinforcing construction 3 of a mesh 3c and bearing bars 3a for uplifting and anchoring made of reflective material. The face surface of the mesh fibres is 3% of the total front surface of the panel. The mesh and anchor bars are completely hidden in the absorptive material. The sound absorptive material 2 is of porous material of spumy and hardened synthetic resin with pores of size 0.5 to 10 mm, which are on the surface opened. The reinforcing mesh 3c bars and the anchor bars 3a are made of steel with anti corrosion surface. Both sides of the panels are flat. Stability of the panels in the acoustic barrier is ensured in the way that they are bedded into vertical steel columns 4 with a vertical groove and they are supported by a horizontal concrete bar EL

Example 4

Fully absorptive acoustic barrier made of panels I of a length of 6 m, a height of 2.4 m and a thickness of 0.2 m showed in pictures 10, 11 and 12. The panels are made of sound absorptive material 2, with a built-in bearing construction 3 of a frame of bars 3a of reflective material. The face surface of the frame bars is 29 % of the total front surface of the panel. 2 % of the frame surface exceeds on the sides from the absorptive material. The absorptive material is placed in the panel in three layers 7, 8 and 9. The surface layers of the absorptive material 2 and 9 are of slabs of porous material of expanded glass with abraded surface. The inner layer of the absorptive material 8 is of slabs made of basalt fibres bound with synthetic resin. The frame is made of reinforced concrete. Both the sides of the panel are flat. Stability of the panels in the acoustic barrier is ensured in the way that they are bedded into vertical steel columns 4 with a vertical groove and they are supported by a horizontal concrete bar 5. Example 5

Fully absorptive acoustic barrier made of panels i of a length of 6 m, a height of 2.4 m and a thickness of 0.2 m showed in pictures 13, 14 and 15. The panels are made of sound absorptive material 2, with a built-in bearing construction 3 of a slab 3b of reflective material with circular holes. The face surface of the slab is 45 % of the total front surface of the panel. 2 % of the slab surface exceeds on the sides from the absorptive material. Both the sides of the panel are flat. The absorptive material 2 consists of crushed recycled rubber granulate with particles sized 1 to 5 mm bound with acrylate bonding agent. The slab 3b is made of reinforced recycled plastic. Stability of the panels in the acoustic barrier is ensured in the way that they are bedded into vertical steel columns 4 with a vertical groove and they are supported by a horizontal concrete bar 5.

Example 6

Fully absorptive acoustic, barrier made of panels i of a length, of 6 m, a height of 2.4 m and thickness of 0.2 rη with a, cut corner showed in pictures 16, 17 and 18. The panels are made of sound absorptive material 2, with a built-in bearing and reinforcing construction 3 of two built-in reinforcing meshes 3b and bearing bars 3a for uplifting and anchoring made of reflective material. The face surface of the mesh fibres is 3% of the total front surface of the panel. The mesh and the- anchor bars are completely hidden in the absorptive material. The absorptive material is placed in the panel in three layers 7, 8 and 9. The surface layers of the absorptive material 7 and 9 are of wooden granulate with particles sized 5 to 10 mm bound with cement bonding .agent. The inner layer of the absorptive material 8 is of wooden granulate with particles sized 2 to 5 mm bound with cement bonding agent. The absorptive material containes dispersed reinforcing fibres. The reinforcing meshes 3b are made of glass fibres and the anchor bars^' 3a are made of compsite material. Both sides of the panels are flat. Stability of the ^'panels in the acoustic barrier is ensured in the way that they are connected on vertical steel columns 4 and they are supported by a horizontal concrete bar 5.

Example 7

Fully absorptive acoustic, barrier made of panels I of a length of 6 m a height of 1.2 m and thickness of 0.16 m showed in pictures 19, 20 and 21. The panels are made of sound absorptive material 2, with a built-in bearing construction 3 of anchor bars 3a for uplifting made of reflective _ material. The face surface of the anchor bars is 1% of the total front surface of the panel. The anchor bars are completely hidden in the absorptive material. The absorptive material consists of lightweight aggregate with particles sized 2 to 4 mm bound with cement bonding agent and contains dispersed reinforcing fibres. The total volume of fibres is 5 % of the total volume of sound absorptive material of the panel. The anchor bars 3a are made of composite material. Both sides of the panels are flat. Stability of the panels in the acoustic barrier is ensured in the way that they are bedded into vertical steel columns 4 with a vertical groove and they are supported by a horizontal concrete bar 5;

Industrial exploatation

Fully absorptive acoustic barriers according to this invention are applicable for construction of screens along roads, railway lines and other noise sources where it is necessary to provide not only sound insulation but also high absorption of the acoustic barriers from one side or from both the sides. The acoustic barrier panels can also be used for permanent or removable acoustic walls,. screening and dividing of internal or external areas.

List of used signs

1 panel

2 sound absorptive material '

3 . bearing or reinforcing construction 3a bars

3b reinforcing mash

3c slab with holes . ^'•.'.^'"

4 vertical columns,_r , . . . .

5 horizontal bar

6 ' layer of a sound absorptive material ' ' ^{; • • '}

7 .front surface; layer of a sound absorptive material . - .. . _, .

8 inner layer of a sound absorptive material

9 back surface layer of a sound absorptive material

10 ribs on the surface of panels

Claims

1. Fully absorptive acoustic barrier, containing sound absorptive and sound reflective material, characterised in that it is made of panels (1), which are made of porous sound absorptive material (2) and contain in the sound absorptive material a bearing or reinforcing construction (3) of slabs (3c) and/or bars (3a) and/or meshes (3b) of reflective material, whose surface in the plane parallel to the front surface of the panel is smaller than 75 % of the total front surface of the panel and which are of at least 50 % of their surface hidden in the sound absorptive material and/or the panels (1) contain fibres as a dispersed reinforcement in the sound absorptive material (2) whose total volume is smaller than 50 % of the total volume of the sound absorptive material of the panel, and the bearing or reinforcing construction is bonded with the sound absorptive material in the panel by means of surface adhesive joint or by means of point mechanical or adhesive joints and the stability of the panels in the acoustic barrier is ensured by their attachment to the supporting construction, whose vertical (4) or horizontal elements (5) surface is covered either with sound reflective material' or partially or fully with an sound absorptive material layer (6) and they are shaped in such a way so that they do not cover more than 50 % of the front or rear surface of the panels (1):

2. Fully absorptive acoustic barrier of claim 1 characterised in that the sound absorptive material (2) in the panels (1) is made of granules with particles sized from 0.1 to 100 mm bound with a bonding agent so that the gaps between the granules are not filled.

3. Fully absorptive . acoustic barrier of claim 1 characterised in that the sound absorptive material (2) in the panels.(l) is made of fibres of a diameter from 0.001 mm to 2 mm bound with a bonding agent so that the gaps between the fibres are not filled.

4. Fully absorptive acoustic barrier of claim 1 characterised in that the sound absorptive material (2) in the panels (1) is made of porous material with pores of a size from 0.1 mm to 20 mm, which are at lόast on the surface opened.

5. Fully absorptive acoustic barrier of claims 1 to 4 characterised in that the sound absorptive material (2) is laid in the panels (1) in one layer, i.e. the sound absorptive material has the same: composition in the whole panel.

6. Fully absorptive acoustic barrier of claims 1 to 4 characterised in that the sound absorptive material (2) is laid in the panels (1) in two or more layers so that the neighbouring layers are of the sound absorptive material of different composition, i.e. a different use of granulate or fibres, a different size of particles or type of granulate, a different size or type of fibres, a different amount or type of bonding agent.

7. Fully absorptive acoustic barrier of claims 1 to 6 characterised in that both, front and rear panel (1) surfaces are flat.

8. Fully absorptive acoustic barrier of claims 1 to 6 characterised in that the front or rear panel (1) surface is profiled with ribs or depths.

9. Fully absorptive acoustic barrier of claims 1 to 6 characterised in that both front and rear panel (1) surfaces are profiled with ribs or depths.

10. Fully absorptive acoustic barrier of claims 1 to 9 characterised in that the sound absorptive material in the bearing construction surface layers is of granulate with particles

, ^■- I -. '-- sized from 0.1 to 100 mm bound with a bonding agent so that the gaps between the fibres are not filled or fibres of a diameter from 0.001 mm to 2 mm bound so that the gaps between the fibres are not filled or of porous material. with pores of a size from 0.1 mm to 20 mm.